I use a 720p 32 inch tv as a media center with a mini attached to it. It works fine for what I do. I can use it as a monitor ok too, assuming all you are doing is basic word processing and internet browsing it works just fine.
If I were you though... I'd get a 1080p (full hd) which has a resolution of 1900 by 1180 or so as opposed to the 720p which is only 1370 by 980 or something close to that. Higher resolution = better picture for computer monitor.
Get the SMALLEST size TV you can find at a 1080 resolution. That's usually a 37 inch or 32 inch. The 32 samsung? that someone mentioned a few posts up looks like a good option. That would give you the highest pixel density which = better picture.
Now... you can easily hook up your mac pro with a dvi to hdmi cord like you said to your tv. However, if you actually purchase a tv you won't need a eyetv tuner, since tvs have it built in, so UNLESS you want to record tv on your mac pro, you could just hook the tv into the cable in your dorm for tv and then switch inputs to the mac pro when you want to use it for downloads, dvds or actual computer work.
If you want to record the tv and send the tv through the mac pro then yes, you will need the eyetv hook up, which works quite well I must say.
... a benefit of this is that you could record a show on your macpro with the eyetv hookup and watch a different channel on your tv's tuner at the same time ... but you will need a 3 dollar cable splitter for that.
Anyway, go with 1080p 32inch tv if possible .... that would be your best option for the best of both worlds. Grab a wireless keyboard and laser mouse and you can surf from bed
You will ofcourse get better resolution (up to 2500 by 1600 or something like that) with a 30 inch MONITOR from dell... but like you said it will be very pricey and if you aren't doing detailed graphics work or anything super precise, or that demands a LOT of pixels and area, then you won't need it.
Go with the TV but get 1080p or FULL hdtv.
GL!
Edit:
the most IDEAL set up IMO is:
This allows you to
-Record shows on your mac pro with the eyetv software
-Watch a show via your tv input while recording something via your eyetv input to your macpro
-Watch tv via your eyetv channel input in a window while working on your mac pro
-Have your mac pro happily working away on something with full power and nothing allocated to your tv tuner since you have one in the tv
-have the best of both worlds
NOTE: Although... if you have the space, you could grab a 32inch LCD at 720p from walmart (vizios are cheap there) and a 22 inch monitor (acer or some cheaper brand if you don't care.. i have one, they are nice)
180 for monitor + 600 for the tv = less then 800... that might work too, nicer monitor for computer AND tv for cheaper then a good 1080p tv.... if you have room in your dorm.
